Headphones are a pair of small listening devices that are designed to be worn on or around the head over the ears of a user. Conventional audio headphones incorporate magnetic-coil loudspeakers, which convert electrical signals into audio signals via air pressure waves. The acoustic waves cause the eardrum membrane to vibrate, which sends the audio signals to the auditory nerves.
Many headphones suffer from sound quality issues. These issues may be exacerbated due to outside noise. Unfortunately, many people have a tendency to increase the volume of the headphones to compensate for the sound quality issues and/or to drown out the outside noise.
With the advent of portable music players, earbuds became a popular alternative to headphones. Earbuds are generally comprised of small speakers which may be inserted into the user's ear canal. Earbuds are typically less expensive than headphones, much lighter and far less bulky. Unfortunately, earbuds deliver inferior sound quality, especially when it comes to bass tones. Earbuds don't filter out external noise very well, so earbud-wearers tend to crank up the volume which may damage the user's hearing.
First generation “hearing aids” are similar to earbuds in that they generally require insertion of the loudspeakers into the ear canals and boosts the dB of the audio signal. Hearing aids are uncomfortable to wear and can potentially further damage the delicate inner-ear components.
Recently, bone-conductive technology has been utilized in both headphones and hearing aids. Bone conduction transmits sound waves through the bones in the user's skull. The vibrations reach the cochlea, or inner ear, which converts them to electrical impulses that travel the auditory nerve to the brain. This is generally accomplished by using a piezoelectric ceramic transducer. To accomplish efficient audio signal transfer, the bone-conductive transducer has to be in direct contact with the skull bone. The headphone/hearing aid is generally installed either in-canal or behind-ear and requires tedious adjustments by an audiologist. Bone-conductive headphones and hearing aids generally require frequent battery replacement. Also, since the ear passage remains unblocked, headphone users generally are able to hear external noises around them.
Therefore, it would be desirable to provide an apparatus and method that overcome the above problems.